## z(3,3 | 3,3) = 27

$I$ | $I$ | $I$ |

$I$ | $\alpha$ | $\alpha^2$ |

$I$ | $\alpha^2$ | $\alpha$ |

The quotient matrix for the finite projective plane of order 3. $I$ is the identity, and $\alpha$ is a 3-cycle.

$I$ | $I$ | $\alpha$ |

$I$ | $\alpha$ | $I$ |

$\alpha$ | $I$ | $I$ |

$I$ is the identity and $\alpha$ is a 3-cycle. The $I$ entries form an extremal 3x3 rectangle-free matrix, showing that the finite projective plane of order 3 is sub-similar.

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